A photovoltaic cell generates electric power from electromagnetic energy (e.g., sunlight) incident thereon. Thin film photovoitaic cells are a class of photovoltaic cells formed by depositing a plurality of thin films onto a substrate, each of which serves one or more specific functions. Thin film photovoltaic cells generally include a first electrical contact layer, one or more films that comprise the active photovoltaic device, and a second electrical contact layer. Depending upon the orientation of the photovoltaic cell, at least one of the first and second electrical contact layers is transparent to allow electromagnetic energy to reach the active device films. If the substrate is an insulating substrate (that is, the substrate has a high electrical resistivity interface for forming one of the first or second electrical contacts thereon), a plurality of thin film photovoltaic cells can be monolithically integrated onto the insulating substrate.
The magnitude of an electric current generated by a thin film photovoltaic cell is proportional the area of the photovoltaic cell. However, the magnitude of a voltage generated by the thin film photovoltaic cell is largely a function of the materials used to form the thin film layers. Accordingly, in order to increase an output voltage magnitude of an array of thin film photovoltaic cells, a plurality of cells may be electrically connected in series.